This invention relates generally to propellers and propeller related vehicles and more particular to vehicles, such as air, land and water vehicles, that use or incorporate propellers to create lift or as a means for propulsion, and for most aspects of the present invention relate to air based vehicles designed for the toy or hobby industry.
While the present invention is related in part to vehicles developed in the toy and hobby industry, the present invention, as will become apparent, may easily be applicable for full sized vehicles. There are many types of vehicles that use propellers as a source of lift or as a means for propulsion. The more common types of these vehicles are air/space based vehicles such as airplanes, helicopters, or unconventional aircraft.
Air-based vehicles such as planes, helicopters and unconventional aircraft that use propellers to create and sustain lift are well known. In general such aircraft, especially aircraft designed for the toy and hobby industry, require complex programming and mechanics to control the flight path and are especially difficult to control. In most instances, controlling these aircraft to fly in a stable horizontal position takes countless hours of practice. Examples of these prior art aircraft may be found in the following U.S. Patents. U.S. Pat. No. 5,609,312 is directed to a model helicopter that describes an improved fuselage with a structure that supports radio-control components, drive train components and such, in an attempt to provide a simple structure. U.S. Pat. No. 5,836,545 is directed to a rotary wing model aircraft that includes a power distribution system that efficiently distributes engine power to the rotary wings and tail rotor system. U.S. Pat. No. 5,879,131 is directed to a main propeller system for model helicopters that are capable of surviving repeated crashes. U.S. Pat. No. 4,604,075 is directed to a toy helicopter that includes a removable control unit, which a user may plug into the toy helicopter.
These toys use at least one propeller rotating in a substantially horizontal plane to create and sustain lift. In addition these xe2x80x9caircraftxe2x80x9d may have another propeller rotating at an angle from the horizontal plane to counter the torque created from the rotating horizontal propeller. Typically the second propeller is rotating in a substantially vertical plane. One problem that arises is when the propellers are rotating in the horizontal plane, variations such as wind or power fluctuations may cause the propeller blades to pitch further causing the aircraft to tip, turn, oscillate or bank. This effect may be compensated for and corrected in various ways with complicated programming and mechanics. However, as mentioned above these have a tendency to make the aircraft too expensive or too difficult to control, especially for children. The ability to even maintain horizontal stability in these aircrafts is extremely difficult.
As such a need exists to improve these aircrafts that utilize propellers to create and sustain lift to overcome the problems identified above. Such a need should be inexpensive and easy to implement. The outcome should further provide for aircrafts that are easy to control or manipulate without the need for complex linkages, servos, gyros or other electromechanical devices.
In addition to the need to improve the stability and control of these aircrafts, there is also an increased need to make such aircraft safer. Oftentimes a child or user is injured when the user comes in contact with a rotating propeller. As such there exists a further need to make the propellers safer.
A propeller related vehicle in accordance with one embodiment of the present invention is described as a helicopter having an airframe housing a motor mechanism for powering a main propeller and a tail rotor. The main propeller is attached to a main drive shaft that extends vertically through the airframe. The helicopter further includes a horizontal stabilizing means attached between the main propeller and the main drive shaft, which permits the main propeller to freely pivot about the main drive shaft independently from the airframe. As such when the main propeller is rotating and the main propeller begins to pitch, a centrifugal force created by the rotation of the main propeller, tends to pivot the main propeller about the horizontal stabilizing means in a manner that offsets the pitch such that the helicopter remains in a substantially horizontal position.
The main propeller of the propeller related aircraft may also exhibit an increased means for self-stabilizing the aircraft. In one embodiment, the main propeller may include a pair of blades extending outwardly from the horizontal stabilizing means. Each blade includes a leading edge, an end proximal to the horizontal stabilizing means, and a distal end. The main propeller also includes a safety arc attached to the proximal and distal ends of each blade and positioned in front of the leading edge of each blade. Furthermore, the safety arc has a diameter, which transitions from a relatively flat horizontal surface by the proximal end into a wider vertical surface by the distal end.
In another embodiment, the main propeller may include a pair of blades extending outwardly from the horizontal stabilizing means along a horizontal plane. Each blade has a leading edge, an end proximal to the horizontal stabilizing means and a distal end. A safety arc is also provided and attached to the proximal and distal ends of each blade and positioned in front of the leading edge of each blade. The main propeller also has a pair of flybars extending outwardly from the horizontal stabilizing means along the horizontal plane. As such when the main propeller is rotating and the main propeller begins to pitch, the flybars having an increased centrifugal force created by the rotation thereof will tend to pivot the blades about the horizontal stabilizing means in a manner that offsets the pitch such that the helicopter remains in a substantially horizontal position.
In another embodiment, the main propeller includes a crossbar joint pivotally attached to the horizontal stabilizing means. A pair of blades extends outwardly along a horizontal plane from the blade joint, wherein each blade has an end proximal to the crossbar joint and a distal end. A pair of crossbars extends outwardly from the crossbar joint along the horizontal plane. Each crossbar has an end proximally secured to the crossbar joint and an end distal thereto. A circular safety ring is secured to the distal ends of each crossbar and has pivots for receiving the distal ends of each blade. A flybar is extended outwardly both from a leading edge and a trailing edge defined in each blade. Each flybar extends along the horizontal plane, wherein when the main propeller is rotating and the main propeller begins to pitch, the flybars having an increased centrifugal force created by the rotation thereof will tend to pivot the blades about the horizontal stabilizing means in a manner that offsets the pitch such that the helicopter remains in a substantially horizontal position.
In another embodiment, the main propeller includes a blade joint pivotally attached to the horizontal stabilizing means. Two pair of blades are extended outwardly along a horizontal plane from the blade joint, such that one pair of blades is perpendicular to the other pair of blades. Furthermore each pair of blades may pivot independently of the other pair. Each blade has an end proximal to the blade joint and a distal end. A circular safety ring includes pivots for receiving the distal ends of each blade. A flybar is extended outwardly from a leading edge defined in each blade, wherein when the main propeller is rotating and the main propeller begins to pitch, the flybars having an increased centrifugal force created by the rotation thereof will tend to pivot the blades about the horizontal stabilizing means in a manner that offsets the pitch such that the helicopter remains in a substantially horizontal position.
In addition thereto the flybars may include weighted ends to increase the centrifugal force created by the rotation thereof. The main propeller described above may be used in other propeller related vehicles since each exhibits a means for stabilizing the propeller in a single plane, or since the main propellers include safety rings or arcs that decrease the likelihood a user may be injured by a rotating propeller.
Numerous advantages and features of the invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, and from the accompanying drawings.